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1.
We studied physiognomy‐specific (i.e., gaps vs. understory) responses of birds to low harvest (18.7 m3/ha), reduced‐impact logging by comparing 3500 mist net captures in control and cut blocks of an Amazonian terra firme forest in Brazil at 20–42 mo postharvest. Species richness did not differ significantly between control (92 species) and cut (85) forest based on rarefaction to 1200 captures. Fifty‐six percent of all species were shared between control and cut forest, compared to the 64 percent shared between control blocks. Higher captures of nectarivores and frugivores in cut forest likely occurred as a consequence of postharvest resource blooms. Higher captures of some insectivores in cut as compared to control forest were unexpected, attributable to increased wandering or shifts from association with midstory to understory as a consequence of habitat alteration. Logging influenced capture rates for 21 species, either consistently, or via positive interaction with physiognomy or time (13 species higher in cut forest and 8 species higher in control forest). Cut understory sites had lower diversity (H′) and scaled dominance than understory and gap sites in control forest. Temporal changes in captures may have resulted from successional dynamics in cut forest: two guilds and three species increased in abundance. Increases in abundances of guilds and particular species were more prevalent in control than in cut forest, suggesting that logging displaced birds to control forest. In general, the effects of logging were relatively minor; low harvest rates and reduced‐impact methods may help to retain aspects of avian biodiversity in Amazon forest understories.  相似文献   

2.
The bat fauna of the Mora excelsa-dominated rainforest in the Victoria-Mayaro Forest Reserve (VMFR) in south-east Trinidad was assessed over a six-week period. Trapping effort totaled 271 mist net hours and caught 143 bats of 22 species at a rate of one bat every two net-hours. Simpsons diversity index (1/D) was 1.28 for primary Mora forest and extrapolation using Chaos' estimator, a non-parametric method, estimated the total number of species as 39. Phyllostomid bats of the subfamilies Phyllostominae and Stenodermatinae were well represented, and frugivores predominated in number, accounting for 77% of all captures in primary forest. The most abundant bat, the ground-storey frugivore, Carollia perspicillata, accounted for 43% of all captures in primary forest and, in contrast to most bats, was also abundant on man-made paths through the forest. Four species not previously recorded from the reserve, Tonatia bidens, Trachops cirrhosus, a Myotis sp., and the rare Phylloderma stenops, were captured, bringing the total number of bats species known from the reserve to 35. Thus, over half (52%) of Trinidad's 67 bat species occur in this one forest reserve, making it a high priority area for effective protection and management.  相似文献   

3.
Fragmentation is a major threat factor for plant–frugivore communities in tropical and subtropical forests. Resulting changes in the distribution of traits within these communities, e.g., a loss in large‐bodied frugivores, may lead to strong changes in plant–frugivore interactions in fragmented forests. Yet, we still lack a thorough understanding of the interplay between forest fragmentation, the trait‐composition of communities and resulting plant–frugivore interactions on a community‐scale. In a fragmented South African landscape comprising different forest categories—i.e., continuous natural forest, forest fragments surrounded by natural grassland, and forest fragments surrounded by sugarcane—we investigated the relationship between communities of fruiting plants and their frugivore visitors in response to forest fragmentation, as well as the interactive effects of forest fragmentation and fruit size of the plants on the number of frugivore visitors and their body size. Neither the fruit size of plant nor the body mass of frugivore communities differed between natural forest sites and forest fragments. Moreover, in‐depth analyses of frugivore assemblages visiting plant species revealed no effect of forest category on the number of frugivore visits or their mean body mass. The number of visits and body mass of frugivores were merely determined by the crop and fruit size of the focal plant species. Overall, our results suggest that frugivory of plant species with differently sized fruits was not reduced in forest fragments. Thus, fragments with high fruit availability may be key elements maintaining the functional connectivity of a heterogeneous forest landscape.  相似文献   

4.
Species richness and diversity of rodents and insectivores were investigated at relict forest patches of Mukogodo, Laikipia, Kenya using Sherman's live traps and pitfall traps. Two hundred and nineteen individuals were captured in 3021 trap‐nights. There were eleven species in two taxonomic groups, Rodentia and Insectivora. Two other rodent species were sighted but not captured. Thirteen bats belonging to four species (Epomophorous wahlbergi, Pipistrellus kuhlii, Scotophilus dingani and Nycteris thebaica) were opportunistically trapped using mist nets. Two of the four species accumulation curves for forest patches did not reach an asymptote. Species richness and diversity were highest at Kurikuri compared with other patches because of habitat variability. The results support the prediction that forest disturbance and degradation lead to an increase in generalist species as compared with specialists and highlight the importance of relict afromontane forests in the conservation of small mammals in Kenya.  相似文献   

5.
Previous studies have used home range size to predict a species’ vulnerability to forest fragmentation. Northern bearded saki monkeys (Chiropotes satanas chiropotes) are medium-bodied frugivores with large home ranges, but sometimes they reside in forest fragments that are smaller than the species’ characteristic home range size. Here we examine how travel and spatial patterns differ among groups living in forest fragments of 3 size classes (1 ha, 10 ha, and 100 ha) versus continuous forest. We collected data in 6 research cycles from July–August 2003 and January 2005–June 2006 at the Biological Dynamics of Forest Fragments Project (BDFFP), north of Manaus, Brazil. For each cycle, we followed the monkeys at each study site from dawn until dusk for 3 consecutive days, and recorded their location. Although bearded saki monkeys living in 10-ha and 1-ha fragments had smaller day ranges and traveled shorter daily distances, they traveled greater distances than expected based on the size of the forest fragment. Monkeys in the small fragments revisited a greater percentage of feeding trees each day, traveled in more circular patterns, and used the fragments in a more uniform pattern than monkeys in the continuous forest. Our results suggest that monkeys in the small fragments maximize their use of the forest, and that the preservation of large tracts of forest is essential for species conservation. Species with large home ranges sometimes inhabit forest fragments, but doing so can alter behavior, demographics, and ecology, and the monkeys may be vulnerable to stochastic events.  相似文献   

6.
Large‐seeded plants are especially vulnerable to the loss of seed dispersers in small forest fragments. The palm Attalea humilis goes against this trend by reaching high abundances in small remnants. Productivity, seed dispersal and seed predation of A. humilis were investigated in two large (2400 and 3500 ha) and three small (19, 26 and 57 ha) Atlantic Forest fragments in southeastern Brazil. Palms in the small fragments produced more female inflorescences, resulting in a higher fruit production in these places. Seed dispersal rates were higher in the large fragments, where scatter hoarding was more frequent. Scolytine beetles were the main seed predators and damaged a larger number of seeds in small fragments, but predation by rodents and bruchine beetles was low irrespective of fragment size. As scolytines do not necessarily kill the seeds, low predation by bruchines and rodents, together with its own high productivity, allow A. humilis to be more abundant in small fragments despite the scarcity of its main dispersers. This increased abundance, by its turn, can increase competitive interactions between A. humilis and other plants in small fragments. Thus, abundance patterns of A. humilis are a good example of fragmentation affecting the balance of ecological interactions in a complex way, emphasizing the role of preserving ecological processes for conserving biodiversity in fragmented tropical landscapes. Abstract in Portuguese is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   

7.
Due to their role in seed dispersal, changes in the community of phyllostomid bats have direct consequences on ecological succession. The objective of this work was to document changes in the structure of bat assemblages among secondary successional stages of tropical rain forest in Chiapas, Mexico. Bats were mist-netted at ground level during 18 months in 10 sites belonging to 3 successional stages: four sites represented early succession (2–8 years of abandonment), four intermediate succession (10–20 years of abandonment), and two late succession (mature old-growth forest).We captured 1,179 phyllostomids comprising 29 species. Phyllostomid species richness was 17 (58% of all species) in the early stage, 18 (62%) in the intermediate stage and 24 (83%) in the late stage. The late successional mature forest possessed nine species that were exclusively found there, whereas early and intermediate successional stages contained only one exclusive species. Sturnira lilium, Artibeus lituratus, Carollia perpicillata, Artibeus jamaicensis and Glossophaga soricina represented 88% of all captured phyllostomid bats. Frugivores made up more than 90% of the species captured in early and intermediate successional stages and 84% in late successional forest. The Bray–Curtis index of dissimilarity showed a replacement of species through successional stages with the largest dissimilarity between early and late stages, followed by intermediate and late, and the lowest dissimilarity between early and intermediate stages. The number of gleaning insectivore species increased during succession. The carnivorous guild was exclusively found in the late stage (three species). We conclude that the late successional mature forest was the main reservoir for the gleaning insectivore and carnivore guilds; however, early and intermediate successional stages possessed a great diversity of species including many frugivores.  相似文献   

8.
Habitat fragmentation could alter ecological traits including species trophic habits. Here, we used carbon and nitrogen stable isotope ratios to establish differences in isotopic niche width and food resource use between forest fragments and the continuous forest for the phyllostomid frugivorous bat Artibeus lituratus. Using mist nests, we captured bats from two forest fragments and two sites in continuous forest, and sampled from each individual captured three body tissues with contrasting turnover rates (skin, muscle, and liver). Samples were collected between February and March (austral summer) and between August and September (austral winter). In addition, in each sampling site and season we collected potential food resources (fruits and insects) consumed by our A. lituratus. Our findings indicate that A. lituratus had a predominantly omnivorous diet, with high consumption of insects during summer in forest fragments. The increasing consumption of insects in these fragments seems to have led to a wider isotopic niche, in relation to the continuous forest. Because A. lituratus is typically a seed disperser, changes in trophic habits in the forest fragments from frugivory to insectivory may diminish their role in forest regeneration. Abstract in Portuguese is available with online material.  相似文献   

9.
We compared the seed fate of two animal‐dispersed, large‐seeded timber species (Dipteryx panamensis [Fabaceae] and Carapa guianensis [Meliaceae]) in logged and fragmented forests with that for continuous forest in northeastern Costa Rica. For both species, we quantified rates of seed removal (an index of vertebrate predation) and the fate of dispersed seeds (those carried away from their original location that either germinated or were not subsequently removed within three months). We predicted that (1) fewer seeds would be dispersed by vertebrates in fragmented forest than in continuous forest due to low population abundances after hunting and/or loss of suitable habitat, and (2) seed predation rates would be higher in forest fragments than in continuous forest due to high abundance of small‐bodied seed consumers. We compared three forest fragments currently managed for timber (140–350 ha) and a large reserve of continuous forest (La Selva, 1500 ha and connected to a national park). An exclusion experiment was performed (seeds placed in the open vs. seeds within semipermeable wire cages; 5 cm mesh size) to evaluate the relative roles of large and small animals on seed removal. Seed germination capacity did not differ among all four sites for both species. Removal of Dipteryx seeds was higher in forest fragments (50% removal within 10 days and related to the activity of small rodents) compared to La Selva (50% removal after 50 days). Also, more Dipteryx seeds were dispersed at La Selva than in fragmented forests. Contrary to our predictions, removal of Carapa seeds was equally high among all four sites, and there was a trend for more seeds of Carapa to be dispersed in fragments than in La Selva. Our results suggest that fragmentation effects on tree seed fate may be specific to species in question and contingent on the animal biota involved, and that management strategies for timber production based on regeneration from seed may differ between forest patches and extensive forests.  相似文献   

10.
The impacts of forest fragmentation on the pteridophyte communities of the Una region of Bahia, Brazil, were investigated by comparing species richness and ensemble diversity among areas of large forest fragments (>900 ha), small forest fragments (<100 ha), and landscape matrix. We inventoried the pteridophytes below 1 m in height in interiors of small fragments, interiors of large fragments (control areas), edges of fragments, edges of continuous forest, capoeiras (initial stages of forest regeneration) and cabrucas (cocoa plantations). All ferns were collected following the plot method (plots of 120×10 m, each). Sampling units were established in the six main ecotypes of the Una region. These units were allocated within three sampling blocks of 5 per 5 km, which were chosen in order to include the largest forest patches that still remain. Results suggest that fragmentation has a negative impact on species richness at the matrix and the edges of forest remnants. A similar negative matrix end edge effect is reported for diversity of those sites measured by the α Log-series Index. However, small forest fragments have pteridophyte species richness and diversity rates similar to large ones so they should be considered of utmost importance to the conservation of forest-related species in the region.  相似文献   

11.
Forest fragmentation can lead to reductions in food availability, especially for some large‐bodied tropical mammals such as spider monkeys. During a 15\xE2\x80\x90mo period, we assessed the diet of Geoffroyi's spider monkey (Ateles geoffroyi) in continuous forest and fragments in the Lacandona region, southern Mexico, and related differences in diet to differences in vegetation structure and composition. We found that both forest types presented top food species for monkeys (e.g., Spondias spp., Brosimum alicastrum), but the sum of the importance value index of these species and the density of large trees were lower in fragments than in continuous forest. We also found that, compared with continuous forest, monkeys in fragments diversified their overall diet, increased consumption of leaves, and reduced the time they spent feeding on trees in favor of more time feeding on hemiepiphytes (particularly Ficus spp.) and palms, both of which were common in fragments. We attribute these changes to the relative food scarcity of the most favored feeding plants in forest fragments. Overall, our findings suggest that monkeys are able to adjust their diet to food availability in fragments, and thus persist in small‐ and medium‐sized fragments. Although it is unlikely that the small size of two of the three study fragments (14 and 31 ha) can maintain viable populations of monkeys in the long term, they may function as stepping stones, facilitating inter‐fragment movements and ultimately enhancing seed dispersal in fragmented landscapes.  相似文献   

12.
ABSTRACT Large‐scale transformation of forested landscapes is a major factor in loss of biological diversity in the American tropics. Investigators examining the responses of species to deforestation rarely control for variation in the amount of forest relative to other habitats at the landscape‐level. Bellavista Reserve on the western slope of the Andes in Ecuador is located between similar‐sized areas of pristine, protected forest, and deforested landscapes. We used strip‐transect counts and mist netting to evaluate habitat use by passerine birds in a habitat mosaic consisting of abandoned pastures, forest edges, forest fragments, and large blocks of interior tropical montane cloud forest (TMCF). During 3600 net hours, we had 1476 captures, including 346 recaptures. Of 78 species captured in mist nets, 30 had sufficient counts for Poison Rate Regression (PRR) modeling (a statistical method for comparing counts). Twelve species (40%) had capture patterns indicative of an affinity for mature TMCF, and 6 species (20%) had significantly higher counts in degraded areas (forest edge, forest fragment, and regenerating pastures) than in interior TMCF. The remaining 40% showed no significant bias in detection among habitats. Combined with strip‐count data, our results suggest that about 38% of the 119 species sampled at the Bellavista Reserve occur primarily in mature TMCF, avoiding edges and early second‐growth forest. Populations of these species may be vulnerable to further loss, fragmentation, and degradation of TMCF and, as such, deserve additional study and a place on lists of species of conservation concern.  相似文献   

13.
Studies comparing the abundance of frugivorous bats in shade‐coffee plantations and forest fragments report contradictory results, and have not taken into account the landscape context in which coffee plantations are immersed. Variables of population composition such as abundance, sex proportion, and reproductive condition, together with biological tags (i.e., bat fly prevalence), can provide information about spatiotemporal dynamics of habitats used by bats. In the central part of Veracruz, Mexico, we compared population variables and ectoparasite prevalence of the highland yellow‐shouldered bat (Sturnira ludovici) in two landscapes, one dominated by shade‐coffee plantations and another by forest fragments. Comparing these attributes between these two landscapes will increase our knowledge about the role of this agro‐ecosystem in the conservation of this species, which is an important seed disperser of cloud forest vegetation. Total abundance and proportion of females was greater in forest fragments than in coffee plantations, whereas the percentage of reproductive females and bat fly prevalence was similar between landscapes. Our results show that landscapes with forest fragments harbor the greatest abundance of S. ludovici, but shade‐coffee plantations also are utilized by S. ludovici and likely adjacent forest remnants provide enough food resources for this species and other frugivores. Moreover, this study provides more evidence documenting the importance of preserving the last cloud forest fragments in the central region of Veracruz, Mexico, and suggests that using shade‐coffee plantations to connect forest fragments may be an effective way of maintaining populations of S. ludovici and likely other volant frugivores.  相似文献   

14.
Tropical forests worldwide are being fragmented at a rapid rate, causing a tremendous loss of biodiversity. Determining the impacts of forest disturbance and fragmentation on tropical biotas is therefore a central goal of conservation biology. We focused on bird communities in the interior (>100 m from forest edge) of forest fragments (300, 600, and 1200 ha) in the lowlands of Papua New Guinea and compared them with those in continuous forest. We surveyed bird communities using point counts, mist‐netting, and random walks, and measured habitat and microclimate characteristics at each site. We also surveyed leaf‐dwelling arthropods, butterflies, and ants, and obtained diet samples from birds to examine food availability and food preferences. We recorded significantly fewer bird species per point in the 300‐ha forest fragment than in other study sites. Overall, we recorded 80, 84, and 88 species, respectively, in forest fragments, and 102 in continuous forest. Frugivores (especially large frugivores) and insectivores had lower species richness in forest fragments than continuous forest. Our results did not support the food scarcity hypothesis, that is, the decline of insectivorous birds in forest fragments is caused by an impoverished invertebrate prey base. We also found no significant differences among forest fragments and continuous forest in microclimates of forest interiors. Rather, we found that microhabitats preferred by sensitive birds (i.e., 30% of species with the strongest preferences for continuous forest) were less common in forest fragments (19%–31% of points) than in continuous forest (86% of points). Our results suggest that changes in microhabitats may make forest fragments unsuitable for sensitive species. However, limited dispersal capabilities could also make some species of birds less likely to disperse and occupy fragments. In addition, impoverished food resources, size of the forest fragment, or hunting pressure could contribute to the absence of large frugivorous birds in forest fragments. The forest fragments in our study, preserved as village‐based protected areas, were not large enough to sustain the bird communities found in continuous forest. However, because these fragments still contained numerous bird species, preservation of such areas can be an important component of management strategies to conserve rainforests and birds in Papua New Guinea.  相似文献   

15.
Forest fragmentation is viewed as a serious threat to primates, yet whether or not it can disrupt food resources and cause energetic stress remains largely untested. I present the results of a 12-mo study of the feeding ecology of Propithecus diadema in fragmented and continuous forest at Tsinjoarivo, eastern Madagascar. Two continuous forest groups had higher dietary diversity and ate more fleshy fruit, but during the dry season, diversity was reduced and they relied heavily on mistletoe (Bakerella clavata). In contrast, 2 groups in fragments employed the lean season strategy of eating mistletoe year-round; the fruiting tree species that sustain continuous forest groups through the rainy season were largely absent. As expected, intersite dietary overlap was highest in the dry season. The level of specialization was high: fragment groups devoted 30–40% of feeding time to Bakerella clavata, compared to 28–30% in continuous forest. The major characteristic of Bakerella clavata enabling it to be an important fallback or staple resource, or both, is its extended phenology. The difference in resource utilization between sites may have important implications for nutritional status, as well as ranging and social behavior, largely owing to the small size and high abundance of feeding patches of Bakerella. Understanding resource shifts in fragments can shed light on socioecological questions by providing comparisons between continuous forest and fragment populations with differing diets and resource distributions. In addition, understanding dietary shifts in fragments can aid in species-specific conservation efforts, while contributing to a better understanding of the considerable interspecific variability of primates in responses to fragmentation.  相似文献   

16.
As tropical forest fragmentation accelerates, scientists are concerned with the loss of species, particularly those that play important ecological roles. Because bats play a vital role as the primary seed dispersers in cleared areas, maintaining healthy bat populations is critical to natural forest regeneration. Observations of foraging bats suggest that many Neotropical fruit‐eating species have fairly general habitat requirements and can forage in many different kinds of disturbed vegetation; however, their roosting requirements may be quite different. To test whether or not general foraging requirements are matched by equally broad roosting requirements, we used radiotelemetry to locate roost sites of two common frugivorous bat species (Sturnira lilium and Artibeus intermedius) in a fragmented forest in southeastern Mexico. Sturnira lilium roosted inside tree cavities and selected large‐diameter roost trees in remnant patches of mature forest. Fewer than 2 percent of trees surveyed had a mean diameter equal to or greater than roost trees used by . S. lilium, Artibeus intermedius roosted externally on branches and vines and under palm leaves and selected roost trees of much smaller diameter. Compared to random trees, roost trees chosen by A. intermedius were closer to neighboring taller trees and also closer in height to these trees. Such trees likely provide cryptic roosts beneath multiple overlapping crowns, with sufficient shelter from predators and the elements. While males of A. intermedius generally roosted alone in small trees within secondary forest, females roosted in small groups in larger trees within mature forest and commuted more than three times farther than males to reach their roost sites. Loss of mature forest could impair the ability of frugivorous bats to locate suitable roost sites. This could have a negative impact on bat populations, which in turn could decrease forest regeneration in impacted areas.  相似文献   

17.
The agricultural matrix surrounding forested areas serves critical functions as dispersal corridors and alternate habitat for wildlife. Agricultural intensification, however, can reduce the conservation value of these areas. To evaluate the effects of agroecosystem management on bat assemblages, we studied the abundance and diversity of leaf-nosed bats (family: Phyllostomidae) in southwestern Chiapas, Mexico, a landscape dominated by shade coffee agroforestry. During 2104 mist-net hour (MNH), we captured 3167 bats of 27 phyllostomid species. Total species richness in each land-use type varied from 24 species in forest fragments to 22 species in commercial shade polycultures. Although the cumulative observed species richness showed little change in response to management intensity, the number of bats captured per MNH declined significantly in the more intensively managed (i.e., low-shade monocultures) plantations. Intensively managed coffee plantations had lower phyllostomid diversity and species similarity, and had lower proportions of nectarivorous and animalivorous bats. Among frugivores, the proportion of large (>25 g) frugivores captured increased with management intensity. Recapture frequency was significantly higher than expected in forest fragments, and lower than expected in more intensively managed coffee. Our results suggest that less intensively managed coffee agroforests can serve as valuable feeding and commuting areas for most leaf-nosed bats, and that maintaining forest fragments in agricultural landscapes contributes to bat diversity. Declines in populations of gleaning insectivores, however, could compromise natural suppression of insect pests in these agricultural areas.  相似文献   

18.
Habitat loss and modifications affect biodiversity, potentially contributing to outbreaks of infectious diseases. We evaluated if the patch sizeinfragmented areas of Atlantic Forest in southeastern Brazil influences the diversity of forest birds and consequently the prevalence of ticks on birds and the rickettsial infection of these ticks. During 2 years, we collected ticks from birds in 12 sites: four small forest patches (80–140 ha), four large ones (480–1,850 ha), and four forest control areas within the much larger Morro do Diabo State Park (~36,000 ha). A total of 1,725 birds were captured (81 species, 24 families), from which 223 birds were infested by 2,339 ticks of the genus Amblyomma, mostly by the species A. nodosum. Bird diversity and richness were higher in larger than smaller forest fragments. The prevalence of ticks on birds was inversely correlated with bird diversity and richness. Among 174 A. nodosum tested for rickettsial infection by polymerase chain reaction, 51 were found to be infected by Rickettsia bellii or Rickettsia parkeri. However, tick infection rates by Rickettsia spp. were not statistically different between forest patch sizes. The higher prevalence of ticks on birds in degraded patches might be caused by a dominance of a few generalist bird species in small patches, allowing an easier transmission of parasites among individuals. It could also be related to more favorable microclimatic conditions for the free-living stages of A. nodosum in smaller forest fragments.The higher burden of ticks on birds in smaller forest fragments is an important secondary effect of habitat fragmentation, possibly increasing the likelihood of Rickettsia contagion.  相似文献   

19.
The Cerrado is considered one of the 25 biodiversity hotspots in the world by conservation organizations. There are few studies on bat taxonomic groups for this biome. Herein we present a bat survey employing mist nets in the protected area of a private natural heritage reserve Reserva Particular do Patrimônio Natural Pousada das Araras, located in the west-central Brazil. We investigate the hypothesis that the Cerrado habitat complexity plays a role on the different structuring forces in bat ecological communities. Bats represent a diversity of trophic levels, and they occupy a wide range of available Cerrado habitats and microhabitats. The patterns and processes we discuss represent the factors influencing coexisting species of bats in different habitats and their implications for conservation. We captured 758 individuals of 25 species belonging to four families. Phyllostomidae was the dominant family, represented by 20 species (80%). The average recapture rate was 6.2%, and the species with most proportional recapture was A. caudifer. Greater species richness was observed among bats with predominantly insectivore habits, followed by frugivores. Glossophaga soricina was a dominant species, with about 30% of the captures. There was seasonal variation relating to the number of bats captured, with greater bat frequency occurring during the wet season, although some species occurred at higher rates during the dry season, such as C. perspicillata and S. lilium. Sanguivore bats were abundant, reflecting the availability of shelters and food supply (livestock) in the surrounding area. Compared to other surveyed areas, Pousada das Araras may be considered of high species diversity, supplanting the majority of known Cerrado studied areas. Apparently Cerrado favours the occurrence of insectivore species, with emphasis on the foliage-gleaning insectivores belong to the subfamily Phyllostominae. This study indicates that apparently the conservation of the Cerrado savanna fragments can support a considerable diversity of bat species.  相似文献   

20.
The interaction between granivorous scatterhoarding mammals and plants is a conditional mutualism: scatterhoarders consume seeds (acting as predators), but the movement of seed by scatterhoarders may contribute to dispersal (acting as mutualists). Understanding the ecological factors that shape this relationship is highly relevant in anthropogenically disturbed tropical forests where large‐bodied frugivores are extirpated. In such forests, large‐seeded trees that once depended on these frugivores for dispersal may now only have scatterhoarders as prospective dispersers. We studied Carapa oreophila (Meliaceae) in an Afromontane forest, to test the hypotheses that the proportion of seeds immediately consumed or hoarded (dispersed) would vary over a disturbance gradient. Temporal replication also afforded exploration of how habitat effects might vary with food availability. Using a Bayesian framework, we demonstrate that seeds were more likely to be hoarded in less disturbed forest, irrespective of temporal variation in food abundance. In contrast, forest disturbance only appeared to increase seed predation in temporal replicates that coincided with sustained food availability. These results highlight the potential variability in the dynamics between plants and scatterhoarders over fine temporal scales, elucidating possible ecological scenarios where scatterhoarders might act as mutualists (contributing positively to plant recruitment). Our study also fills important knowledge gaps about the importance of scatterhoarders as dispersers in tropical forests depleted of large‐bodied frugivores, particularly in Africa where scatterhoarding mutualisms have not been extensively studied.  相似文献   

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